From
the BBC» :
Buddleia: The plant that dominates Britain's railways
More people are buying buddleia for their gardens, but it's classified as an invasive species and is a problem on British railways.It's hard to walk by a railway line in Britain and not see buddleia. Along fences by the tracks and almost any patch of waste ground, you will notice the long, slender clumps of flowers, usually lilac but also blue, deeper purple or white, at the end of long, arching branches.
BBC weather forecaster Peter Gibbs says the mild, wet winter will have improved germination and growth this year, especially in areas where water normally drains away quickly, such as derelict urban sites. "Buddleia is an opportunist that's always ready to capitalise on any slight advantage."
Sprouting from seemingly every derelict building, it stakes an increasingly plausible claim for the title of Britain's national flower.
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The plant can cause damage to buildings, such as crumbling brickwork - its tiny wind-blown seeds can germinate in decaying mortar.
And the problems caused by buddleia to the management of the rail network are described by the Non-Native Species Secretariat as "significant".
Buddleia on the tracksNetwork Rail says buddleia has a habit of growing in walls where it can interfere with overhead power lines and obscure signals. While it does not cause "serious" problems such as blocking train lines, it does have a habit of popping up in "annoying places" where removing it takes up valuable time and resource.
The company cuts down large buddleia before removing or killing the stumps, sprays small buddleia with herbicide, and uses weed-killing trains to keep the network clear, while staff use portable sprayers at stations.
